In recent years, higher efficiency and productivity have been in increasing demand for processing of color photographic materials. This tendency is particularly remarkable in the preparation of color prints, and a reduction in print processing time has been strongly desired to provide shorter finishing times.
A color print finishing stage generally comprises exposure and color development processing, and subsequent desilverization, washing and/or stabilization and drying.
The use of a highly sensitive photographic material results in a reduction in exposure time. On the other hand, in order to shorten the color development time, it is necessary to use, in combination, a photographic material capable of rapid development with a compatible processing solution or processing method.
Known techniques for solving such problems include processing a color photographic material containing an emulsion having a high silver chloride content (high silver chloride emulsion), in place of silver chlorobromide emulsions having a high silver bromide content and which have been widely used for photographic materials for color prints (color photographic paper). For example, PCT International Publication No. WO87/ 04534 discloses a method of rapidly processing color photographic paper comprising a high silver chloride emulsion with a color developing solution substantially free from sulfite ion and benzyl alcohol.
In addition to the above patent, JP-A-61-70552 (the term "JP-A" as used therein means an "unexamined published Japanese patent application") discloses a method for reducing the quantity of replenisher for a developing solution, in which the replenisher is added in an amount such that there is no overflow of the developing bath during development, using a high silver chloride content color photographic material. Furthermore, JP-A-63-106655 discloses a method of processing a high silver chloride content color photographic material with a color developing solution containing a hydroxylamine compound and chloride ion at a specific minimum concentration to provide stable processing.
Thus, by use of a high silver chloride content emulsion or by adapting the developing solution, the development time can be shortened from 3.5 minutes (for example, color processing CP-20, Fuji Photo Film Co., Ltd.) to 45 seconds (for example, color processing CP-40FAS, Fuji Photo Film Co., Ltd., total processing time: 4 minutes).
The development function can be renewed by replenishing a developing solution with a developing replenisher depending on the consumption or deterioration state of the developing solution. In general, the developing solution is replenished with a developing replenisher containing a developing agent, a preservative, a chelating agent, a salt, an alkaline component and the like all in the same one solution, depending on the quantity of photographic material to be processed.
However, the solubility of the developing agent in a high pH replenisher solution containing the preservative or the alkaline component is less than the solubility in a low pH solution such as a neutral or acidic solution. As a result, it is difficult to prepare a highly concentrated replenisher solution. For this reason, when the developing solution must be replenished with a large amount of the developing agent, the replenishment rate must be increased. Accordingly, an increased amount of waste liquid overflows from the developing tank.
In recent years, it has been desired to reduce or prevent the generation of waste liquid in photographic processing, due to the complexity of treatment needed to make the photographic processing waste liquid environmentally sound. Also, when the developing solution is replenished, the concentration of the developing agent in the developing replenisher is conceivably raised to reduce the replenishment rate such that the developing solution does not overflow. However, it is difficult to increase the amount of the developing agent dissolved in solution as long as the developing replenisher contains high pH components such as the alkaline component.
Recently, the rapid processing of color photographic paper which does not generate polluting waste liquid has been desired. Accordingly, investigators have sought to reduce the replenishment rate of color developing solutions as applied to rapid processing of color photographic paper using silver halide emulsions containing 90 mol % or more of silver chloride, to thereby reduce the waste liquid amount of the color developing solution containing a large quantity of harmful substances. For this purpose, it has been proposed to separately replenish the developing solution with a low pH replenisher mainly containing a color developing agent and a high pH replenisher containing components other than the color developing agent, such that the concentration of the color developing agents can be increased in the low pH replenisher. The replenishment rate can therefore be reduced, which results in the discharge of little or no waste liquid.
The developing solution is replenished with such a replenisher, depending on the quantity of photographic material to be processed, the pH of the developing solution, the change in solution amount due to evaporation, and the change in composition due to air oxidation. When the developing solution is replenished by concurrently admixing the low pH replenisher or concentrated developing solution and the high pH replenisher containing components other than the developing agent, a precipitate results which not only lowers the replenishment function, but also introduces the problem of treating the precipitate.
Furthermore, it has been found that the developing agent in the low pH replenisher gradually deteriorates during long storage and adversely affects photographic images.